Carton blank



FIG. 1 is a top plan view of a carton blank showing my new design, the bottom plan view being the same in appearance;

FIG. 2 is a left side elevation thereof, the right side being the same in appearance;

FIG. 3 is a front elevation thereof; and,

FIG. 4 is a rear elevation thereof.

The solid lines in the top plan view represent micro cuts and the dashed lines represent old lines, in the blank structure 

The ornamental design for a carton blank, as shown and described. 